4,4-Diallyl curcumin bis(2,2-hydroxymethyl)propanoate ameliorates nonalcoholic steatohepatitis in methionine-choline-deficient diet and Western diet mouse models.

Nonalcoholic steatohepatitis (NASH) is a progressive form of nonalcoholic fatty liver disease (NAFLD) that causes severe liver damage, fibrosis, and scarring. Despite its potential to progress to cirrhosis or hepatic failure, approved drugs or treatments are currently unavailable. We developed 4,4-diallyl curcumin bis(2,2-hydroxymethyl)propanoate, also known as 35e, which induces upregulation of mitochondrial proteins including carnitine palmitoyltransferase I (CPT-I), carnitine palmitoyltransferase II, heat shock protein 60, and translocase of the outer mitochondrial membrane 20. Among these proteins, the upregulated expression of CPT-I was most prominent. CPT-I plays a crucial role in transporting carnitine across the mitochondrial inner membrane, thereby initiating mitochondrial ß-oxidation of fatty acids. Given recent research showing that CPT-I activation could be a viable pathway for NASH treatment, we hypothesized that 35e could serve as a potential agent for treating NASH. The efficacy of 35e in treating NASH was evaluated in methionine- and choline-deficient (MCD) diet- and Western diet (WD)-induced models that mimic human NASH. In the MCD diet-induced model, both short-term (2 weeks) and long-term (7 weeks) treatment with 35e effectively regulated elevated serum alanine aminotransferase (ALT)/aspartate aminotransferase (AST) concentrations and histological inflammation. However, the antisteatotic effect of 35e was obtained only in the short-term treatment group. As a comparative compound in the MCD diet-induced model, curcumin treatment did not produce significant regulatory effects on the liver triglyceride/total cholesterol, serum ALT/AST, or hepatic steatosis. In the WD-induced model, 35e ameliorated hepatic steatosis and hepatic inflammation, while increasing serum AST and hepatic lipid content. A decrease in epididymal adipose tissue weight and serum free fatty acid concentration suggested that 35e may promote lipid metabolism or impede lipid accumulation. Overall, 35e displayed significant antilipid accumulation and antifibrotic effects in the two complementary mice models. The development of new curcumin derivatives with the ability to induce CPT-I upregulation could further underscore their efficacy as anti-NASH agents.

The association of protein-bound methionine sulfoxide with proteomic basis for aging in beech seeds.

BACKGROUND: European beech (Fagus sylvatica L.) trees produce seeds irregularly; therefore, it is necessary to store beech seeds for forestation. Despite the acquisition of desiccation tolerance during development, beech seeds are classified as intermediate because they lose viability during long-term storage faster than typical orthodox seeds. In this study, beech seeds stored for short (3 years) or long (20 years) periods under optimal conditions and displaying 92 and 30% germination capacity, respectively, were compared. RESULTS: Aged seeds displayed increased membrane damage, manifested as electrolyte leakage and lipid peroxidation levels. Analyses have been based on embryonic axes, which contained higher levels of reactive oxygen species (ROS) and higher levels of protein-bound methionine sulfoxide (MetO) in aged seeds. Using label-free quantitative proteomics, 3,949 proteins were identified, of which 2,442 were reliably quantified pointing to 24 more abundant proteins and 35 less abundant proteins in beech seeds under long-term storage conditions. Functional analyses based on gene ontology annotations revealed that nucleic acid binding activity (molecular function), ribosome organization or biogenesis and transmembrane transport (cellular processes), translational proteins (protein class) and membranous anatomical entities (cellular compartment) were affected in aged seeds. To verify whether MetO, the oxidative posttranslational modification of proteins that can be reversed via the action of methionine sulfoxide reductase (Msr) enzymes, is involved in the aging of beech seeds, we identified and quantified 226 MetO-containing proteins, among which 9 and 19 exhibited significantly up- and downregulated MetO levels, respectively, in beech seeds under long-term storage conditions. Several Msr isoforms were identified and recognized as MsrA1-like, MsrA4, MsrB5 and MsrB5-like in beech seeds. Only MsrA1-like displayed decreased abundance in aged seeds. CONCLUSIONS: We demonstrated that the loss of membrane integrity reflected in the elevated abundance of membrane proteins had a higher impact on seed aging progress than the MetO/Msr system. Proteome analyses enabled us to propose protein Sec61 and glyceraldehyde-3-phosphate dehydrogenase as potential longevity modulators in beech seeds.

Adrenal pheochromocytoma impacts three main pathways: cysteine-methionine, pyrimidine, and tyrosine metabolism. / è‚¾ä¸Šè ºå—œé“¬ç»†èƒžç˜¤å½±å“ä¸‰æ¡ä¸»è¦ä»£è°¢é€šè·¯ï¼šåŠèƒ±æ°¨é ¸-è›‹æ°¨é ¸ä»£è°¢ã€å˜§å•¶ä»£è°¢å’Œé ªæ°¨é ¸ä»£è°¢é€šè·¯.

Pheochromocytomas and paragangliomas (PPGLs) cause symptoms by altering the circulation levels of catecholamines and peptide hormones. Currently, the diagnosis of PPGLs relies on diagnostic imaging and the detection of catecholamines. In this study, we used ultra-performance liquid chromatography (UPLC)/quadrupole time-of-flight mass spectrometry (Q-TOF MS) analysis to identify and measure the perioperative differential metabolites in the plasma of adrenal pheochromocytoma patients. We identified differentially expressed genes by comparing the transcriptomic data of pheochromocytoma with the normal adrenal medulla. Through conducting two steps of metabolomics analysis, we identified 111 differential metabolites between the healthy group and the patient group, among which 53 metabolites were validated. By integrating the information of differential metabolites and differentially expressed genes, we inferred that the cysteine-methionine, pyrimidine, and tyrosine metabolism pathways were the three main metabolic pathways altered by the neoplasm. The analysis of transcription levels revealed that the tyrosine and cysteine-methionine metabolism pathways were downregulated in pheochromocytoma, whereas the pyrimidine pathway showed no significant difference. Finally, we developed an optimized diagnostic model of two metabolites, L-dihydroorotic acid and vanylglycol. Our results for these metabolites suggest that they may serve as potential clinical biomarkers and can be used to supplement and improve the diagnosis of pheochromocytoma.

An insight into the pharmacology of cysteine/methionine containing peptide drugs.

Since last century, peptides have emerged as potential drugs with >90 FDA approvals for various targets with several in the pipeline. Sulphur, in peptides is present either as thiol (-SH) from Cys or thioether from Met. In this review, all the peptides approved by FDA since 2000 containing sulphur have been included. Among them ∼50 % contains disulphide bridges. This clearly demonstrates the significance of disulphide bonds in peptide drugs. This can be achieved synthetically by using orthogonal protecting groups (PGs) for -SH. These PGs are compatible with Solid Phase Peptide Synthesis (SPPS), which is still the method of choice for peptide synthesis. The orthogonal PGs used for Cys thiol side chain protecting for disulphide bond formation have been included which are currently in use both by academia and industry from small scale to large scale synthesis. In addition, the details of the FDA approved drugs containing Cys and Met (or both) have also been discussed.

Methionine and Leucine Promote mTOR Gene Transcription and Milk Synthesis in Mammary Epithelial Cells through the eEF1Bα-UBR5-ARID1A Signaling.

Amino acids are essential for the activation of the mechanistic target of rapamycin (mTOR), but the corresponding molecular mechanism is not yet fully understood. We previously found that Met stimulated eukaryotic elongation factor α (eEF1Bα) nuclear localization in bovine mammary epithelial cells (MECs). Herein, we explored the role and molecular mechanism of eEF1Bα in methionine (Met)- and leucine (Leu)-stimulated mTOR gene transcription and milk synthesis in MECs. eEF1Bα knockdown decreased milk protein and fat synthesis, cell proliferation, and mTOR mRNA expression and phosphorylation, whereas eEF1Bα overexpression had the opposite effects. QE-MS analysis detected that eEF1Bα was phosphorylated at Ser106 in the nucleus and Met and Leu stimulated p-eEF1Bα nuclear localization. eEF1Bα knockdown abrogated the stimulation of Met and Leu by mTOR mRNA expression and phosphorylation, and this regulatory role was dependent on its phosphorylation. Akt knockdown blocked the stimulation of Met and Leu by eEF1Bα and p-eEF1Bα expression. ChIP-PCR detected that p-eEF1Bα bound only to the -548 to -793 nt site in the mTOR promoter, and ChIP-qPCR further detected that Met and Leu stimulated this binding. eEF1Bα mediated Met and Leu' stimulation on mTOR mRNA expression and phosphorylation through inducing AT-rich interaction domain 1A (ARID1A) ubiquitination degradation, and this process depended on eEF1Bα phosphorylation. p-eEF1Bα interacted with ARID1A and ubiquitin protein ligase E3 module N-recognition 5 (UBR5), and UBR5 knockdown rescued the decrease of the ARID1A protein level by eEF1Bα overexpression. Both eEF1Bα and p-eEF1Bα were highly expressed in mouse mammary gland tissues during the lactating period. In summary, we reveal that Met and Leu stimulate mTOR transcriptional activation and milk protein and fat synthesis in MECs through eEF1Bα-UBR5-ARID1A signaling.

Intracranial residual lesions following early intensification in a patient with T-cell acute lymphoblastic leukemia: a case report.

BACKGROUND: T-cell acute lymphoblastic leukemia (T-ALL) tends to involve central nervous system (CNS) infiltration at diagnosis. However, cases of residual CNS lesions detected at the end of induction and post early intensification have not been recorded in patients with T-ALL. Also, the ratio and prognosis of patients with residual intracranial lesions have not been defined. CASE PRESENTATION: A 9-year-old boy with T-ALL had multiple intracranial tumors, which were still detected post early intensification. To investigate residual CNS lesions, we used 11C-methionine (MET)-positron emission tomography. Negative MET uptake in CNS lesions and excellent MRD status in bone marrow allowed continuing therapies without hematopoietic cell transplantation. CONCLUSIONS: In cases with residual lesions on imaging studies, treatment strategies should be considered by the systemic response, direct assessment of spinal fluid, along with further development of noninvasive imaging methods in CNS. Further retrospective or prospective studies are required to determine the prognosis and frequency of cases with residual intracranial lesions after induction therapy.

Deprivation of methionine inhibits osteosarcoma growth and metastasis via C1orf112-mediated regulation of mitochondrial functions.

Osteosarcoma is a malignant bone tumor that primarily inflicts the youth. It often metastasizes to the lungs after chemotherapy failure, which eventually shortens patients' lives. Thus, there is a dire clinical need to develop a novel therapy to tackle osteosarcoma metastasis. Methionine dependence is a special metabolic characteristic of most malignant tumor cells that may offer a target pathway for such therapy. Herein, we demonstrated that methionine deficiency restricted the growth and metastasis of cultured human osteosarcoma cells. A genetically engineered Salmonella, SGN1, capable of overexpressing an L-methioninase and hydrolyzing methionine led to significant reduction of methionine and S-adenosyl-methionine (SAM) specifically in tumor tissues, drastically restricted the growth and metastasis in subcutaneous xenograft, orthotopic, and tail vein-injected metastatic models, and prolonged the survival of the model animals. SGN1 also sharply suppressed the growth of patient-derived organoid and xenograft. Methionine restriction in the osteosarcoma cells initiated severe mitochondrial dysfunction, as evident in the dysregulated gene expression of respiratory chains, increased mitochondrial ROS generation, reduced ATP production, decreased basal and maximum respiration, and damaged mitochondrial membrane potential. Transcriptomic and molecular analysis revealed the reduction of C1orf112 expression as a primary mechanism underlies methionine deprivation-initiated suppression on the growth and metastasis as well as mitochondrial functions. Collectively, our findings unraveled a molecular linkage between methionine restriction, mitochondrial function, and osteosarcoma growth and metastasis. A pharmacological agent, such as SGN1, that can achieve tumor specific deprivation of methionine may represent a promising modality against the metastasis of osteosarcoma and potentially other types of sarcomas as well.

Copper(I)-nitrene platform for chemoproteomic profiling of methionine.

Methionine plays a critical role in various biological and cell regulatory processes, making its chemoproteomic profiling indispensable for exploring its functions and potential in protein therapeutics. Building on the principle of rapid oxidation of methionine, we report Copper(I)-Nitrene Platform for robust, and selective labeling of methionine to generate stable sulfonyl sulfimide conjugates under physiological conditions. We demonstrate the versatility of this platform to label methionine in bioactive peptides, intact proteins (6.5-79.5 kDa), and proteins in complex cell lysate mixtures with varying payloads. We discover ligandable proteins and sites harboring hyperreactive methionine within the human proteome. Furthermore, this has been utilized to profile oxidation-sensitive methionine residues, which might increase our understanding of the protective role of methionine in diseases associated with elevated levels of reactive oxygen species. The Copper(I)-Nitrene Platform allows labeling methionine residues in live cancer cells, observing minimal cytotoxic effects and achieving dose-dependent labeling. Confocal imaging further reveals the spatial distribution of modified proteins within the cell membrane, cytoplasm, and nucleus, underscoring the platform's potential in profiling the cellular interactome.

N-acetyl-l-methionine dietary supplementation improves meat quality by oxidative stability of finishing Angus heifers.

Methionine plays a vital role in protein synthesis, and regulation of antioxidant response in ruminants. This study aimed to assess the effects of dietary supplementation with N-acetyl-l-methionine (NALM), which serves a source of rumen-protected methionine, on growth performance, carcass traits, meat quality, and oxidative stability. Sixty Angus heifers (initial body weight = 408 ± 51.2 kg, 15-18 months) were stratified by body weight and randomly assigned to four dietary treatments: a control group (0% NALM), and experimental groups receiving diets containing 0.125%, 0.25%, and 0.50% NALM (dry matter (DM) basis), respectively. The experiment included a 2-week adaptation and a 22-week data and sample collection period. Results indicated that blood urea nitrogen in the plasma of the 0.25% NALM group was lower compared to the control and the 0.50% NALM groups (P = 0.02). The plasma methionine (P = 0.04), proline (P < 0.01), and tryptophan (P = 0.05) were higher in the 0.25% and 0.50% NALM groups, as well as the methionine and proline in the muscle of the 0.25% NALM group (P < 0.01). The muscle pH (P < 0.01) was increased by supplementing 0.25% and 0.50% NALM in diets but decreased the lactate (P < 0.01). The 0.25% NALM group also increased a* (P = 0.05), decreased L* (P = 0.05), drip loss (P = 0.01), and glycolytic potential in the muscle (P < 0.01). The total antioxidant capacity, superoxide dismutase, glutathione peroxidase, catalase, and glutathione in muscle of 0.25% NALM group were higher than that of the control (P < 0.01), and the malondialdehyde and protein carbonyl were lower (P < 0.01). In conclusion, the dietary supplement with NALM improves meat quality by enhancing the antioxidant effect of lipids and proteins.

A role of methionines in the functioning of oxidatively modified fibrinogen.

Posttranslational modifications in fibrinogen resulting from induced oxidation or oxidative stress in the organism can have deleterious influence on optimal functioning of fibrinogen, causing a disturbance in assembly and properties of fibrin. The protective mechanism supporting the ability of fibrinogen to function in ROS-generating environment remains completely unexplored. The effects of very low and moderately low HOCl/-OCl concentrations on fibrinogen oxidative modifications, the fibrin network structure as well as the kinetics of both fibrinogen-to-fibrin conversion and fibrin hydrolysis have been explored in the current study. As opposed to 25 Μm, HOCl/-OCl, 10 µM HOCl/-OCl did not affect the functional activity of fibrinogen. It is shown for the first time that a number of Met residues, AαMet476, AαMet517, AαMet584, BßMet367, γMet264, and γMet94, identified in 10 µM HOCl/-OCl fibrinogen by the HPLC-MS/MS method, operate as ROS scavengers, performing an important antioxidant function. In turn, this indicates that the fibrinogen structure is adapted to the detrimental action of ROS. The results obtained in our study provide evidence for a protective mechanism responsible for maintaining the structure and functioning of fibrinogen molecules in the bloodstream under conditions of mild and moderate oxidative stress.

A novel methionine nanoparticle in broiler chickens: Bioavailability and requirements.

This bioassay evaluated the bioavailability (RBV) of a novel nanoparticle of methionine (nano-Met) relative to DL-methionine (DL-Met), and estimated methionine requirements for both sources in starting broilers. Five supplemental levels (0.05, 0.10, 0.15, 0.20, and 0.25% of diet) of DL-Met or nano-Met were added to a basal diet containing 0.35% standardized ileal digestible (SID) methionine to create 11 experimental diets, including a basal diet and 10 experimental diets containing 0.40, 0.45, 0.50, 0.55, and 0.60% SID-Met, respectively. A total of 825 one-day-old male Ross 308 birds were randomly assigned to 11 treatments with 5 pen replicates and 15 birds each. Body weight gain (BWG), breast meat yield (BMY), and thigh meat yield (TMY) increased (P < 0.001) while feed conversion ratio (FCR) and malondialdehyde (MDA) concentration in meat samples decreased (P < 0.001) with increasing dietary methionine. Based on the slope-ratio method, the RBV of nano-Met relative to DL-Met for BWG, FCR, and TMY were 102 (48-155%; R2 = 0.71), 134 (68-201%; R2 = 0.77), and 110% (27-193%; R2 = 0.55), respectively. Considering the statistical accuracy of the spline models, the estimated values of DL-Met for maximum BWG and nano-Met for maximum TMY were 0.578% and 0.561%, respectively, which were statistically higher than those recommended for commercial settings. The highest effect size of supplemental methionine was on MDA (ƞ2p = 0.924), followed by FCR (ƞ2p = 0.578), BMY (ƞ2p = 0.575), BWG (ƞ2p = 0.430), and TMY (ƞ2p = 0.332), suggesting the potent antioxidant properties of methionine. Our findings suggest that reducing the particle size of DL-Met to nanoparticles could be a promising strategy to enhance the efficiency of methionine supplementation in broilers, an idea that requires further investigation in future research.

Relative biological efficacy of methionine hydroxy analogue-free acid compared to dl-methionine in the broiler chickens.

BACKGROUND: In the broiler's diets based on corn-soya bean meal, methionine (Met) and cystine (Cys), known as sulphur amino acids (SAAs), are the first limiting indispensable amino acids because of their limited presence, which are supplemented with different synthetic sources. Evaluation of the biological effectiveness of these sources can be important in their correct replacement, especially in the starter and growth diets. OBJECTIVES: The current study was done to assess the relative biological efficacy (RBE) of liquid Met hydroxy analogue-free acid (MHA-FA) in comparison with dl-Met (dl-Met) based on broiler performance traits at different levels of digestible SAA in the 1-11 (starter) and 11-25 (grower) days of age periods. METHODS: Two experiments were developed with treatments consisting of a basal diet without Met addition that met the nutrient and energy requirements of broilers with the exception of SAAs (Met + Cys) and five increasing Met doses for both sources (dl-Met and/or MHA-FA), resulting in digestible SAA concentrations from 0.62% to 1.02% of diet in the starter period (Trial 1) and 0.59% to 0.94% of diet in the grower period (Trial 2). The multi-linear regression model and slope ratio method were employed to calculate the RBE of MHA-FA compared with dl-Met for measured variables. RESULTS: In both experiments, the results obtained during the starter and grower periods with the different Met supplementations show significant growth responses to digestible SAAs levels. By increasing dietary dl-Met and/or MHA-FA levels, the growth performance traits and immune responses were improved (quadratic; p < 0.05). The RBE of MHA-FA compared to dl-Met on an equimolar basis was estimated 66%-89% (59%-79% on a weight-to-weight basis). CONCLUSIONS: It is concluded that the RBE of MHA-FA in comparison with dl-Met depends on broiler chicken age and what attribute is being evaluated.

Multitissue transcriptomics demonstrates the systemic physiology of methionine deficiency in broiler chickens.

Methionine (Met) supplementation is common practice in broilers to support nutrition, yet there are gaps in the understanding of its role in systemic physiology. Furthermore, several different Met sources are available that may have different physiological effects. This study evaluated the mode of action of Met deficiency (no Met-supplementation) and supplementation (0.25% DL- or L-Met, 0.41% liquid methionine hydroxy analog-free acid (MHA-FA)), and of Met source (DL-, L- or MHA-FA) in broiler chickens, via host transcriptomics. Biological pathway activation modeling was performed to predict the likely phenotypic effects of differentially expressed genes (DEGs) in tissue samples from the jejunum, liver and breast obtained at 10, 21 and 34/35 d of age from three experiments in a combined analysis. Animal performance data showed that Met deficiency reduced BW, daily BW gain, daily feed intake, and breast yield, and increased feed conversion ratio in all experiments (P < 0.05). Effects of Met deficiency on gene expression were least evident in the jejunum and most evident in the liver and breast, as evidenced by the number of DEG and activated pathways. Activated pathways suggested Met deficiency was associated with inhibited protein turnover, gut barrier integrity, and adaptive immunity functions in the jejunum, that predicted reduced breast yield. There was an interaction with age; in Met-deficient birds, there were 333 DEGs in the jejunum of starter vs finisher birds suggesting young birds were more sensitive to Met deficiency than older birds. In the liver, Met deficiency activated pathways associated with lipid turnover, amino acid metabolism, oxidative stress, and the immune system, whereas in breast, it activated pathways involved in metabolic regulation, hemostasis, the neuronal system, and oxidative stress, again predicting a negative impact on breast yield. In the starter phase, supplementation with DL-Met compared to MHA-FA inhibited gamma-aminobutyric acid activity and oxidative stress in breast tissue. When data from all tissues were integrated, increased expression of a liver gene (ENSGALG00000042797) was found to be correlated with the expression of several genes that best explained variation due to the Met deficiency in jejunum and breast muscle. Some of these genes were involved in anti-oxidant systems. Overall, the findings indicate that impaired growth performance due to Met deficiency results from an array of tissue-specific molecular mechanisms in which oxidative stress plays a key systemic role. Young birds are more sensitive to Met-deficiency and DL-Met was a preferential source of Met than L- or MHA-FA during the starter phase.

Non-alcoholic fatty liver disease changes the expression and activity of hepatic drug-metabolizing enzymes and transporters in rats.

Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver diseases, which can cause serious complications and gradually increase the mortality rate. However, the effects of NAFLD on drug-metabolizing enzymes and transporters remain unclear, which may cause some confusion regarding patient medication. In this study, a NAFLD rat model was constructed by feeding rats with methionine and choline deficiency diets for 6 weeks, and the mRNA and protein levels of drug-metabolizing enzymes and transporter were analyzed by real-time fluorescent quantitative PCR and Western blot, respectively. The activity of drug-metabolizing enzymes was detected by cocktail methods. In the NAFLD rat model, the mRNA expression of phase I enzymes, phase II enzymes, and transporters decreased. At the protein level, only CYP1A1, CYP1B1, CYP2C11, and CYP2J3 presented a decrease. In addition, the activities of CYP1A2, CYP2B1, CYP2C11, CYP2D1, CYP3A2, UGT1A1, UGT1A3, UGT1A6, and UGT1A9 decreased. These changes may be caused by the alteration of FXR, HNF4α, LXRα, LXRß, PXR, and RXR. In conclusion, NAFLD changes the expression and activity of hepatic drug-metabolizing enzymes and transporters in rats, which may affect drug metabolism and pharmacokinetics. In clinical medication, drug monitoring should be strengthened to avoid potential risks.

Dietary supplementation of methionine, lysine, and tryptophan as possible modulators of growth, immune response, and disease resistance in striped catfish (Pangasius hypophthalmus).

The present study investigated the potential role of different essential amino acids (AA) in striped catfish (Pangasius hypophthalmus). Fish (initial weight = 17.91±0.27 g, n = 260) were fed with eight isonitrogenous (30%), and isolipidic diets (6%) formulated to include different combinations of tryptophan (Trp), methionine (Met), and lysine (Lys) (T0: Zero AA, T1: Trp, T2: Lys, T3: Met, T4: Trp+Met, T5: Lys+Trp, T6: Met+Lys, T7: Lys+Trp+Met) for eight weeks. The dose of amino acid supplementation, whether individually or in combination, was 5g of each amino acid per kg of diet. The trial comprised eight treatments, with each treatment consisted of three replicates (n = 10/replicate). At the end of the growth experiment, the highest total body weight, crude protein, digestive enzymatic activity, immune response, and amino acids level were observed in treatments supplemented with amino acids compared to T0. After the growth experiment, fish in all treatments were exposed to Staphylococcus aureus (5×105 CFU/ml). For bacterial challenge trial, the T0 treatment was designated as positive (+ve T0) and negative control (-ve T0). Following the S. aureus challenge, fish fed with amino acids showed a better response to reactive oxygen species and lipid peroxidation, as indicated by the increased levels of catalase and superoxide dismutase. Conversely, the concentration of malondialdehyde gradually decreased in all treatments compared to the +ve T0 treatment. It is concluded that supplementation of amino acids improved the growth, protein content, and immunocompetency against S. aureus in striped catfish. The most favorable outcomes in striped catfish were shown by fish supplemented with T7 diet. These essential amino acids hold potential as efficient supplements for use in the intensive aquaculture for striped catfish.

Methionine inducing carbohydrate esterase secretion of Trichoderma harzianum enhances the accessibility of substrate glycosidic bonds.

BACKGROUND: The conversion of plant biomass into biochemicals is a promising way to alleviate energy shortage, which depends on efficient microbial saccharification and cellular metabolism. Trichoderma spp. have plentiful CAZymes systems that can utilize all-components of lignocellulose. Acetylation of polysaccharides causes nanostructure densification and hydrophobicity enhancement, which is an obstacle for glycoside hydrolases to hydrolyze glycosidic bonds. The improvement of deacetylation ability can effectively release the potential for polysaccharide degradation. RESULTS: Ammonium sulfate addition facilitated the deacetylation of xylan by inducing the up-regulation of multiple carbohydrate esterases (CE3/CE4/CE15/CE16) of Trichoderma harzianum. Mainly, the pathway of ammonium-sulfate's cellular assimilates inducing up-regulation of the deacetylase gene (Thce3) was revealed. The intracellular metabolite changes were revealed through metabonomic analysis. Whole genome bisulfite sequencing identified a novel differentially methylated region (DMR) that existed in the ThgsfR2 promoter, and the DMR was closely related to lignocellulolytic response. ThGsfR2 was identified as a negative regulatory factor of Thce3, and methylation in ThgsfR2 promoter released the expression of Thce3. The up-regulation of CEs facilitated the substrate deacetylation. CONCLUSION: Ammonium sulfate increased the polysaccharide deacetylation capacity by inducing the up-regulation of multiple carbohydrate esterases of T. harzianum, which removed the spatial barrier of the glycosidic bond and improved hydrophilicity, and ultimately increased the accessibility of glycosidic bond to glycoside hydrolases.

Influence of acid-base equilibrium on interactions of some monofunctional coumarin Pd(II) complexes with biologically relevant nucleophiles-comprehensive kinetic study.

This aimed to develop a comprehensive theoretical protocol for examining substitution reaction processes. The researchers used a theoretical quantum-mechanical protocol based on the QM-ORSA approach, which estimates the kinetic parameters of thermodynamically favourable reaction pathways. This theoretical protocol was validated by experimentally investigating substitution mechanisms in two previously synthesised Pd(II) complexes: chlorido-[(3-(1-(2-hydroxypropylamino)ethylidene)chroman-2,4-dione)]palladium(II) (C1) and chlorido-[(3-(1-(2-mercaptoethylamino)-ethylidene)-chroman-2,4dione)]palladium(II) (C2), along with biologically relevant nucleophiles, namely L-cysteine (l-Cys), L-methionine (l-Met), and guanosine-5'-monophosphate (5'-GMP). Reactions were investigated under pseudo-first-order conditions, monitoring nucleophile concentration and temperature changes using stopped-flow UV-vis spectrophotometry. All reactions were conducted under physiological conditions (pH = 7.2) at 37 °C. The reactivity of the studied nucleophiles follows the order: l-Cys > l-Met > 5'-GMP, and the reaction mechanism is associative based on the activation parameters. The experimental and theoretical data showed that C2 is more reactive than C1, confirming that the complexes' structural and electronic properties greatly affect their reactivity with selected nucleophiles. The study's findings have confirmed that the primary interaction occurs with the acid-base species L-Cys, mostly through the involvement of the partially negative sulfur atom (87.2%). On the other hand, C2 has a higher propensity for reacting with L-Cys-, primarily through the partially negative oxygen atom (92.6%). The implementation of this theoretical framework will significantly restrict the utilization of chemical substances, hence facilitating cost reduction and environmental protection.

Targeting methionine metabolism in cancer: opportunities and challenges.

Reprogramming of methionine metabolism is a conserved hallmark of tumorigenesis. Recent studies have revealed mechanisms regulating methionine metabolism within the tumor microenvironment (TME) that drive both cancer development and antitumor immunity evasion. In this review article we summarize advancements in our understanding of tumor regulation of methionine metabolism and therapies in development that target tumor methionine metabolism. We also delineate the challenges of methionine blockade therapies in cancer and discuss emerging strategies to address them.

Extensive Shrinkage and Long-term Stable Disease in a Teenage Female Patient With High-grade Glioma Treated With Temozolomide and Radiation in Combination With Oral Recombinant Methioninase and a Low-methionine Diet.

BACKGROUND/AIM: Gliomas are the most common and recalcitrant malignant primary brain tumors. All cancer types are addicted to methionine, which is a fundamental and general hallmark of cancer known as the Hoffman effect. Particularly glioma cells exhibit methionine addiction. Because of methionine addiction, [11C]-methionine positron emission tomography (MET-PET) is widely used for glioma imaging in clinical practice, which can monitor the extent of methionine addiction. Methionine restriction including recombinant methioninase (rMETase) and a low-methionine diet, has shown high efficacy in preclinical models of gliomas, especially in combination with chemotherapy. The aim of the present study was to determine the efficacy of methionine restriction with oral rMETase (o-rMETase) and a low-methionine diet, combined with radiation and temozolomide (TMZ), on a teenage female patient with high-grade glioma. CASE REPORT: A 16-year-old girl was diagnosed with high-grade glioma. Magnetic resonance imaging (MRI) showed a left temporal-lobe tumor with compression to the left lateral ventricle and narrowing of sulci in the left temporal lobe. After the start of methionine restriction with o-rMETase and a low-methionine diet, along with TMZ combined with radiotherapy, the tumor size shrunk at least 60%, with improvement in the left lateral ventricle and sulci. The patient's condition remains stable for 19 months without severe adverse effects. CONCLUSION: Methionine restriction consisting of o-rMETase and a low-methionine diet, in combination with radiation and TMZ as first-line chemotherapy, were highly effective in a patient with high-grade glioma.

Targeting Methionine Addiction Combined With Low-dose Irinotecan Arrested Colon Cancer in Contrast to High-dose Irinotecan Alone, Which Was Ineffective, in a Nude-mouse Model.

BACKGROUND/AIM: Colorectal cancer (CRC) is the third-leading cause of death in the world. Although the prognosis has improved due to improvement of chemotherapy, metastatic CRC is still a recalcitrant disease, with a 5-year survival of only 13%. Irinotecan (IRN) is used as first-line chemotherapy for patients with unresectable CRC. However, there are severe side effects, such as neutropenia and diarrhea, which are dose-limiting. We have previously shown that methionine restriction (MR), effected by recombinant methioninase (rMETase), lowered the effective dose of IRN of colon-cancer cells in vitro. The aim of the present study was to evaluate the efficacy of the combination of low-dose IRN and MR on colon-cancer in nude mice. MATERIALS AND METHODS: HCT-116 colon-cancer cells were cultured and subcutaneously injected into the flank of nude mice. After the tumor size reached approximately 100 mm3, 18 mice were randomized into three groups; Group 1: untreated control on a normal diet; Group 2: high-dose IRN on a normal diet (2 mg/kg, i.p.); Group 3: low-dose IRN (1 mg/kg i.p.) on MR effected by a methionine-depleted diet. RESULTS: There was no significant difference between the control mice and the mice treated with high-dose IRN, without MR. However, low-dose IRN combined with MR was significantly more effective than the control and arrested colon-cancer growth (p=0.03). Body weight loss was reversible in the mice treated by low-dose IRN combined with MR. CONCLUSION: The combination of low-dose IRN and MR acted synergistically in arresting HCT-116 colon-cancer grown in nude mice. The present study indicates the MR has the potential to reduce the effective dose of IRN in the clinic.